The following is to provide guidance for software developers, both
inside and outside the Apache projects, to understand what they need
to do to apply the
Apache License,
Version 2.0 (ALv2), to their own or the ASF's software, including
source code, documentation, and binary distributions. It is not intended
to supplant or otherwise modify any of the terms within the license itself.
Other Apache-related licenses and updates regarding compatibility
with other open source licenses will be posted on the
Apache Licenses page.
http://www.apache.org/licenses/
Contents
The ALv2 consists of a set of copyright and patent licensing terms
that are documented in the
LICENSE-2.0.txt
file. One of those terms provides for attribution notices to be included
with a work in a
NOTICE
file, such that the attribution notices will remain, in some form, within
any derivative works. The license terms are written in such a way
that they can be used by anyone, not just the ASF, and can be
applied by reference to the versioned license terms.
To apply the ALv2 to a new software distribution, include one copy of the
license text by copying the file:
http://www.apache.org/licenses/LICENSE-2.0.txt
into a file called LICENSE in the top directory of your distribution.
If the distribution is a jar or tar file, try to add the LICENSE file
first in order to place it at the top of the archive.
In addition, a NOTICE file should be included in the same directory as
the LICENSE file. The NOTICE should include only those attribution notices
that are required by any part of the entire distribution. For Apache
projects and those redistributing ASF software, the NOTICE file must
contain the sentence:
This product includes software developed by
The Apache Software Foundation (http://www.apache.org/).
The license is applied to each source file (code and documentation,
but excluding the LICENSE and NOTICE files) by including a short copyright
notice at the top, as demonstrated by the
boilerplate
notice provided in the appendix.
Source files contributed to or developed as part of an ASF project should
begin with a copyright notice like
Copyright 2004 The Apache Software Foundation.
or
Copyright 1999-2004 The Apache Software Foundation.
or
Copyright 2002,2004 The Apache Software Foundation.
where the years given start with the first publication year of the file
contents (the authored expression) and include a range of years for
each year that new significant content (derivative work) is published
within the file. Since the ASF publishes its code in public source
repositories (using Subversion), we generally want to include a
range of years starting with the year of origin. Do not worry about
consistency in the first year -- it is not supposed to be uniform
and should never be dated prior to the year of first creation.
If the distribution also contains source files not owned by the ASF,
such as third-party libraries, then be sure to leave their licenses intact.
In some cases, you may want to ask the author(s) of third-party code to
relicense it under the 2.0 license, since that will simplify the distribution.
Otherwise, you should append their license(s) to the LICENSE file at the
top of the distribution, or at least put a pointer in the LICENSE file to
the third-party license. In all cases, be sure to obey the licensing
constraints of the original author. If that is not possible, then do not
redistribute their work.
You want to achieve a final distribution as described above for
applying the license to new software. There is
at least one tool for automatically converting an existing 1.1-licensed
file (or tree of files) to the new license. It is available to
committers under the committers/relicense module in the source repository.
Please be careful to preserve the existing copyright dates and avoid applying
the license to third-party files. For Apache software, we strongly
recommend checking the diffs of each file and commit only one directory at a
time (bottom-up) so that the changes can be verified without overwhelming
reviewers.
If the code is owned or distributed by the Apache Software Foundation, then
the answer is Yes. The 2.0 license was approved by the ASF board
in their January 2004 meeting. As part of that meeting, the board mandated
that all ASF software distributions must be converted to the new license
by March 1, 2004.
If the code is not owned by the ASF, then the decision is up to the copyright
owner. Naturally, we strongly recommend that you upgrade to the new license.
All code released after 1 March 2004 must have been converted.
Only if you want the ASF to make a new release of that code after 1 March 2004.
"Dead" branches of code do not have to be updated
Code has to be updated prior to any release after 1 March 2004. However code in the source repository can
remain under the old 1.1 license until such time as you are ready to perform a release.
Note that this applies to any kind of release after 1 March 2004 - including bug fixes.
Only one full copy of the license is needed per distribution. Each source
file only needs to contain the boilerplate notice at:
http://www.apache.org/licenses/LICENSE-2.0.html#apply
No. The new license allows for a NOTICE file that contains such attribution
notices (including the Apache attribution notice). See
http://www.apache.org/licenses/example-NOTICE.txt
for an example that provides all of the notices applicable to the
httpd-2.0 distribution.
No. The only ASF related copyright notice should be for The Apache Software Foundation.
The following text is extracted from an e-mail from Sander Striker. It
describes some of the issues with multiple copyrights. The original e-mail can
be found here.
The number of copyright lines has to be kept down to as few as possible.
A single line with 'Copyright Apache Software Foundation' is prefered.
While multiple copyright lines can coexist, they are undesirable for
the following reasons:
Legal protection
When personal copyrights are mentioned, the ASF can do very little
when it comes to legal protection (nothing we can do when someone
is sued on personal title).
Social aspects
Acknowledgement of contributions per file has shown not to promote
colloborative development.
There is the pattern where people try and touch as many files as
possible to get their name in as many files as possible.
There is also the creation of personal islands within the codebase.
The acknowledgements make this sentiment stronger. It will be
less likely that someone touches a file that is marked as someone
elses domain. This is bad.
This is permitted. However the preference is that the files be called LICENSE and NOTICE.
Yes. All source files should include the copyright notice boilerplate
that indicates it is owned by the ASF and that it is distributed under
the Apache License, Version 2.0.
Applying the Apache License, Version 2.0